use enums in function signatures within typescript definitions

[Treeki]

This is an attempt at fixing #2154 by generating TypeScript definitions that use the correct type for enums within function arguments and return types rather than just number.

I’m quite unfamiliar with this codebase so it’s very possible that my approach will require further tweaks, but I hope it’s at least a good start.

I’ve adapted the backend crate’s codegen module to output the js_name for Enums within the descriptor and likewise adapted the cli-support crate to load that information. To have it appear in the TS definitions, I’ve added AdapterType::Enum(String) which compiles to the same adapter code but carries the name alongside it.

I’ve also added a new pair of files to the typescript_tests crate to handle these cases.

[SebastienGllmt]

Heads up this would conflict with #2631

[daxpedda]

I'm happy to review this after a rebase.

[stefnotch]

@Treeki Would you be interested in finishing this work, or should someone else take over? I'd love seeing this pull request being merged.

[thomasetter]

The underlying issue #2154 seems to have been fixed in #3647.

This PR should therefore probably be closed as it is obsolete.

[daxpedda]

Indeed, thanks!